附着体是继卡环、套筒冠之后的第三大类直接固位体。它不仅解决了卡环由于金属钩暴露而产生的美观缺陷问题 ,而且能在一些特殊情况如基牙倾斜度过大、难以取得共同就位道、余留牙过少且牙周情况不佳、游离缺失等条件时取得良好的固位、稳定效果 ,同时能更合理的调节应力分布情? Attachment is following the ring, sleeve crown after the third largest category of direct retainer. It not only solves the aesthetic defects caused by the exposure of the metal hook, but also can solve the problem of beautiful appearance of the snap ring due to the exposure of the metal hook. In addition, it can be difficult to obtain a joint path in some special cases such as inclination of the abutment, too few residual teeth and poor periodontal condition, When conditions such as obtaining a good retention, the stability effect, at the same time more reasonable regulation of stress distribution?